Mice in the dishwasher

September 12, 2006 12:33 PM

How do we keep mice out of the dishwasher and what might be the health effects of having them in there?

(effects on us, that is -- not on the mice :-)

Mice get into our dishwasher (even when the door is latched). That means that there are mouse droppings in our dishwasher. This happens even when the dishes in there are clean (e.g. If we run the dishwasher when we go to bed at night, there already are droppings in there when we get up in the morning).

They seem to be getting in and out at the bottom of the door somehow, but I can't tell exactly where. When we open the dishwasher, they flee towards the door (i.e. the hinge) and disappear, but if the one who opened the door responds to this by slamming the door then the mouse is often crushed under the bottom of the door. The dishwasher does not leak. Are mice likely to be able to get in and out of any dishwasher or is there some damage here that is allowing access? Put another way: the dishwasher is ancient and I don't mind getting a new one but I want to make sure that this actually addresses the issue (and that I know how to keep them out).

The dishwasher presumably heats the water to a sufficient degree (for a sufficient amount of time) that bacteria are killed, but we have recently had an episode of pinworm in our household. Might the mouse droppings be the source of this infection? After all, if the worms can survive in the gut, hot water might not be so tough. Any other creepy-crawlies we should be worried about?

We are in a townhouse and an adjacent unit is, um, not likely to be free of mice in the foreseeable future. So completely eradicating them from our home is next to impossible, though the dishwasher is the only place it's really a problem, thanks to kitty-power.

posted by anonymous to home & garden (14 comments total)

That is totally bizarre.

Some dishwashers just use hot tap water which may not be hot enough. Some dishwashers heat the water hotter - mine heats water to around 70 deg C I think, which should do a better job.

Having said that, your detergent should wipe anything else out. Most diswasher detergents contain bleach, which should kill anything microbial. I believe bleach is all that is recommended for killing hantavirus, which is found in mouse droppings. If your dishwasher smells bleachy when you open it partway through a cycle, you're probably OK. Cascade, for example, contains bleach, but I would expect every dishwasher detergent does as well.

Getting a new dishwasher is not a bad idea. Or in your case, a new house. Easier said than done. Good luck.
posted by GuyZero at 12:47 PM on September 12, 2006

just treat it like any other mouse problem: trap 'em ... but not in your dishwasher. set up traps in other likely locations to rid yourself of the mouse problem. the fact that they're getting in your dishwasher is kinda gross, but as guyzero mentions, not really a problem.
posted by lester's sock puppet at 12:51 PM on September 12, 2006

It's just my humble opinion, but that sounds as good as a reason to get a new dishwasher as any.

The mice are getting in in such a way that does not cause the dishwasher to leak, while the door is closed? Have you pulled the dishwasher out, to inspect the thing from all angles, and maybe make sure your cabinets aren't rotting away? Seems impossible to me, but obviously, it is happening. Regardless, I can't imagine a new dishwasher where this could happen, and if it did, I'd be taking it right back to the store ASAP (repeatadly, if necessary) until I got one that didn't allow this.
posted by cgg at 1:06 PM on September 12, 2006

we found mouse droppings in our pantry, put out a few traps and never caught the meeses. then one day while using the oven, it started to smoke. i being the clueless first time homeowner did not put 2+2 together, and called in the oven repair guy. he turned the oven on and said "do you smell that?", which smelled like burning hair. by now i think you can guess that yes, we roasted some mice. it was winter and they make a nest in between the inner oven & outer oven wall to keep warm. the smell was god awful. oven guy said it was fixable (if a $700 repair job on a $1200 oven is "fixable"), but not gauranteed that it wouldnt smell when we used it for a while. we opted for a new stove. point of all this is, call the pest control guy now, so you will not have to call an oven guy later.
posted by fumbducker at 1:07 PM on September 12, 2006

Mice in the dishwasher means your dishwasher leaks. This will ultimately be more harmful to your house than the mice themselves. You need to kill the mice with poison and/or traps, and get a new dishwasher.
posted by frogan at 1:20 PM on September 12, 2006

Wait a minute, they're getting into your dishwasher when it's latched shut?? Have you noticed any leaks? If the seal isn't broken on the washer, I'm guessing thier entry is through the unit's drain. Check the drain cover and trap. If there's chewing through the mesh, then that might be the problem. I'd also get the connecting pipes/hoses checked, and find out whether the water heats enough during the cycles. Either way, I'd want a dishwasher repair person to take a good look at the unit, and check to see if you have water damage from a leak. That might end up being an even bigger issue. Yikes.
posted by maryh at 1:21 PM on September 12, 2006

Jinx, frogan!
posted by maryh at 1:22 PM on September 12, 2006

And I know it probably goes without saying, but don't use the washer until you get it checked. If you have a leak in the connecting hose, you'll just be adding to your future misery.
I had a similar problem about 10 years ago; the seal on mine wasn't quite tight enough. And then the ants came... The sight of dirty dishes swarmed with a writhing carpet of ants is an image I'll take with me to my grave. And the little dribble of run-off that came with the ant-sized breach was enough to trash the tile under the unit.
You know, better yet, just get a new washer. Bosch are nice.
posted by maryh at 1:49 PM on September 12, 2006

I also have a Bosch. Very quiet. Best appliance I own.
posted by GuyZero at 2:11 PM on September 12, 2006

You really should get rid of them. The problem with mice is that they are diesase carriers. Deermice are the primary resevoir of Hanta virus in North America. It's not a terribly common disease, but the effects are very severe, so why take the risk?

I think you're looking at a replacement.
posted by bonehead at 2:39 PM on September 12, 2006

I'd just like to touch on the "The dishwasher presumably heats the water to a sufficient degree (for a sufficient amount of time) that bacteria are killed" comment.

This is a common misconception. With ordinary household dishwashers, this has never been the case. A dishwasher is not an autoclave - it makes no attempt to sterilize your dishes with heat. There are specific models that specifically do this, but that feature is always called out, and is more common on commercial grade washers.

As GuyZero mentions, most "ordinary" dishwashers - say, anything that came with an apartment or house when you moved in - only use the hot tapwater. Even the old ones with heating elements along the bottom only used the heating elements to dry the dishes.
posted by Dunwitty at 4:46 PM on September 12, 2006

I believe bleach is all that is recommended for killing hantavirus, which is can be found in mouse droppings.

Just wanted to clarify this point: all mouse droppings most certainly do not contain hantavirus. It's a bit of a crapshoot, but odds are the droppings are just full of bacteria and other nasty-but-won't-eat-your-face things.
posted by Civil_Disobedient at 5:18 PM on September 12, 2006

Awesome question, and by "awesome" I mean nicely weird. I just this evening installed a brand-new dishwasher in Casa de Turducken, and am now intimately familiar with their workings. So, my brain-dump:

1. New appliances are way better than old ones (even as little as 10 years old) in terms of energy efficiency and quietness. If you can afford it, just go to Sears and get yourself a new one. They install 'em, too.

2. If your dishwasher isn't leaking water all over the floor, then the mice aren't getting in through the door. Take a peek down near the base of the unit. No puddles = no mouse entry. The rest of the unit is a big plastic bucket, essentially, so there's no other way to get in. (That said, they may be trying to get OUT thru the door...)

3. If your dishwasher is leaking -- from anywhere -- repair or replace stat. Your house is rotting away as we speak.

4. If no leaks, the only place for Mickey & Co. to enter is through the drain tube. If you have a garbage disposal in your sink, there's a nice mouse-sized hole near the rim for them to enter and shimmy down into the dishwasher.

5. The dishwasher uses hot water from your tap, basically, with the addition (on some models) of an electric heater-ring like the one in a toaster. You can raise the level to autoclave-hot by raising the temp on your water heater -- but this means that you may get scalded by water out of the other faucet(s) in the house.

6. If the mice are coming in thru the drain tube, you'll have the same problem with a new washer. D'oh.
posted by turducken at 11:49 PM on September 12, 2006

I second what everyone else said about the almost certain reality of a leak being worse than the mice. Sustained water damage is very bad... I mean, you don't want to have to rebuild your kitchen when replacing the appliance is all that's needed.

All that stuff about cats getting rid of mice is true in my experience. I live near railroad tracks, not to mention a bar and an empty warehouse, so we didn't have mice when we bought our house but rats. We had traps, both poison and glue, and my husband would occasionally scan the yard for victims and chuck them. Then we got a feral cat who by virtue of living with us stopped the sound of scratching all around us. Now we have two cats and they don't even wait for the rats to come inside to take care of them for us.
posted by frecklefaerie at 6:49 AM on September 15, 2006